Production of saccharide, most of which is glucose and xylose, from cellulose and/or hemicellulose by decomposing plant fibers being biomass, for example, sugar cane trash (bagasse), wood piece or the like, and efficient use of the obtained saccharide as food or fuel, are proposed and practically used. Particularly, the art, wherein the saccharide obtained by decomposing plant fibers is fermented to produce alcohol such as ethanol which serves as fuel, has received attention.
Several methods of producing saccharide such as glucose by separating cellulose and hemicellulose are conventionally proposed (for example, Patent Literatures 1 to 4). Examples of general methods include a method of hydrolyzing cellulose using sulfuric acid such as dilute sulfuric acid or concentrated sulfuric acid, or hydrochloric acid (Patent Literature 1 etc.), a method using cellulase enzyme (Patent Literature 2 etc.), a method using a solid catalyst such as an activated carbon or zeolite (Patent Literature 3 etc.) and a method using pressurized hot water (Patent Literature 4 etc.).
Patent Literature 1: Japanese Patent Application Laid-open (JP-A) No. 08-299000
Patent Literature 2: JP-A No. 2006-149343
Patent Literature 3: JP-A No. 2006-129735
Patent Literature 4: JP-A No. 2002-59118